Tetrahydronaphthostyrils and process of preparing the same



Patented is. 7, 1930 UNITED S A KARL scnrnmncnnn, or Hocrrsr-oN-rHE-ium,AND nns scnnrcnnnmunn Ann-- WALTER xnoss, or BAD-serials, GERMANY,nssmnons 'ro GENERAL nmnmn worms, me, or new YORK, N. Y., a conronn'rronor DELAWARE rn'rmrnnonnrrrrnosr nrns AND rnocnss or PREPARING ran SAMENo Drawing. Application filed November 21, 1927, Serial Ro...234,898,and in Germanyilwovember 25, 1926.

5 that naphthostyril, when reduced in the presence of a catalyst underpressure, can be transformed into tetrahydronaphthostyrils. By thisprocess compounds of the following constitution: a

HN- co are obtainable. v The hydrogenation is advantageously effe'cted1n the presence of an indifferent solvent, such as for instancedecahydronaphthalene of chlorobenzene. On a technica scale,

there may be used as'catalyst a metal of the iron group,'in particularnickel. The. tetrahydronaphthostyrils obtainable according to. ourinvention are important intermediate products for-the manufacture ofdyestuffs and compounds of pharmaceutical ap lication.

' e following example illustrates the invention, but is not intended tolimit it thereto: I

g A mixture-of 16,9 parts by weight of LS I naphthostyril, 150 parts ofdecahydronaphthalene' and 0,5.parts of anickel-catalyst as prepared, forinstance, according to U. S. ap-

plication Sen-No. 123,591 is laced in a bomb provided with a stirrer,whic is then charged with hydrogen at 20 atmospheres ressure and themass is heated At C. t e pressure begins to fall. If the temperature israised gradually to 0., hydrogen is quicklyabsorbed by the mass. Whenthe pressure no longer falls, the whole is allowed to cool and theproduct, which largely conas benzeneor xylene, very sparingly solublecompound as sodium'sa t of the amino-car- When the mother-Iyes ofthefirst and second sists of crystals mixed with the catalyst, isfiltered by suction from the decahydrona hthalene and recrystallizedfrom petrol-et er of the boiling point 120 (ll- C. Thus there areinitially obtained colorless, coarse crystals which, after being againrecrystallized from xylene, melt at 157 C. They are readily soluble inalcohol or glacial acetic acid, sparingly soluble] in hydrocarbons, suchin water. The compound is insoluble in sodium carbonate solution or coldcaustlc'soda I solution; in hot caustic soda solution it dis' solves,after forming, a ellow intermediate boxylic acld of the followingformula: L

" coon This a tan,- then easily be diazotizedi The correspondingtetrahydro-naphthostyril has, therefore, the following constitution:

crystallization are allowed to stand for-a rolonged time, a secondcompound crystal izes out which on repeated recrystallization fromalcohol melts at 164 C. This com ound forms small colorless needlescollecte into druses and can be split up somewhat more diificultly thanthe initial compound b boiling with a caustic soda solution. Unli e theimtial compound the secondary crystallizaco The temperature may varybetween 80 '.C.-

tion product when treated with boiling caustic soda yields without therebein any formation of a yellow intermediate bo y an aminocarboxylic acidof the following s Which cannot be transformedinto an arcmatic diazocompound. The seconds tetrahydronaphthostyril, therefore,'has t efollowing constitution:

HN-CO H Instead of nickel, there may be used as lyst another metal, forinstance platinum or palladium. As solvent ma also serve chloroe formulastyrils of the the'following formula;

6. Theprocess of preparingptetrahydro naphthostyrils which comprlsestreating naphthostyril with hydrogen under ressure ofbetween 20 and 30atmospheres in t e presence of .decahydronaphthalene and a mckelcatalyst.

' 7. As new Products, 'tetrahydronaphthoollowing-formula: I

rm o

wherein one of the six-memb ered rings is an aromatic rin said productsbeing spht up in the five-mem ered ring by means of ot caustic sodasolution with formation of colorless amino-carboxylici acid salts. I

8. As a new product, the naphthostyril of HN-CO enzene instead of decaydronaphthalene,

and 180 C. and correspondingl the pressure between and 50 atmosp eresespecially between and atmospheres. As regards the temperature, it is ageneral rule that it may be the lower the more eflicient the catalystis.

We claim: I

1. The process of preparing ;tet'rahydronaphthostyrils which compnsestreating naphthostyril with hydro on under pressure in the presence ofan indi erent solvent and tures.

forming, when recrystallized from xylene colorless crystals melting at157 C. an

dissolving readily in alcohol and glacial acetic acid, very difiicultlyin water, yielding when treated with hot caustic soda solution a 7 saltof a diazotizable amino-carboxylic acid.

'In testimony whereof, we aiiix our signa- KARL SGHIRMACHER.

HANS SOHLICHENMAIER. WALTER KROSS.

a hydrogenating metal catalyst of the iron group.

2. The process of. preparing tetrahydronaphthostyril with h drogen undera pressure of between 10 an atmospheres in the presence ofdecahydronaphthalene and a.

nic5ke lfizlatalyst. f h d e process 0 prepa tetra ronaphthostyrilswhich mg y etween 20 and 30 atmos heres m e presence of decahydronaphthene and a hydropnatingmetalcatalystoftheirongroup.

comprises treating ngphthostyril with hydrogen under ressure. o

